I. Field of Invention
This invention relates to railroad transportation systems, and in particular, to intermodal rail truck and coupling systems to enable intermodal containers to be efficiently and effectively adapted to rail use and being allowable to be coupled to conventional rail cars. The present invention forms an improvement to the co-pending application referred to above, which was a continuation-in-part to U.S. Pat. No. 4,416,571, and is an improvement to that patent also.
II. Problems in the Art
The above-referred to U.S. Pat. No. 4,416,571, commonly owned by the applicant, reveals a truck and rail transportation system which allows intermodal containers to be efficiently converted from truck to rail modes and visa versa by utilizing semi-tractor-type fifth-wheel pancakes which are pivotable to allow kingpins on the intermodal containers to be received and pivotally secured. As is discussed in the co-pending application, to preserve the integrity of the system, the load line, or stress line along the train of containers and cars must be at as close to a uniform height as possible. Because of the high stresses generated by rail transportation, an uneven load line creates drastic problems which could lead to stress failure, damage, or other detrimental effects.
The co-pending application discusses how the disparity in load line throughout the system disclosed in the patent can be lessened. However, it still does not present a uniform load line the exact height of the load line through conventional rail cars. Conventional rail cars distribute the load line through the main stress carrying center beam of the rail cars, which is along their longitudinal axis and which is at the height of the conventional rail car couplers at opposite ends of conventional rail cars. Thus, the device discussed in the co-pending application is still subject to eccentric and disaligned stress forces caused by the fifth-wheel connection to the intermodal containers being offset with respect to the plane of connection of the prime mover of the train to the intermodal rail truck.
Furthermore, the co-pending application discusses the need for the fifth-wheel pancake assemblies to be raisable and pivotable to allow intermodal containers to be raised to a height where a highway mode tractor and tandem axle rear wheels can be inserted thereunder and thereafter transversely removed from the pancakes.
It is therefore an object of this invention to provide an intermodal rail truck and coupling system which obtains a uniform load line along the various intermodal containers and conventional rail cars attached to one another.
A further object of this invention is to provide an intermodal rail truck and coupling system which automatically and remotely couples intermodal containers or conventional rail cars to produce the uniform load line at the height of a conventional rail car load line.
A further object of this invention is to provide an intermodal rail truck and coupling system which automatically and remotely couples intermodal containers or conventional rail cars to produce the uniform load line at the height of a conventional rail car load line and which also allows for required pivoting of intermodal containers or conventional rail cars as to one another to facilitate rail car pivoting around curves in the rails.
Another object of this invention is to provide an intermodal rail truck and coupling system which has conventional rail car couplers which are lowerable below the conventional load line of conventional rail cars when not in use.
Another object of this invention is to provide an intermodal rail truck and coupling system which has pivotable and raisable fifth-wheel pancake members which are positionable so that intermodal containers pivotally attached thereto can be positioned so as to be along said load line of conventional rail cars and then which are raisable to pivot and raise said intermodal containers so that they can be removed transversely of longitudinal axis of the intermodal rail truck for highway mode purposes.
A further object of this invention is to provide an intermodal rail truck and coupling system which can couple two intermodal containers, two conventional rail cars, or an intermodal container and a conventional rail car while at the same time maintaining a uniform load line therethrough, at the height of a conventional load line of a conventional rail car.
A further object of this invention is to provide an intermodal rail truck and coupling system whereby the maintenance of a uniform load line, the lowering of the conventional coupler means, and the raising and pivoting of the fifth-wheel pancakes can be achieved automatically by remote control.